DURHAM, N.C. -- Duke engineers have devised a way to improve the efficiency of lithotripsy -- the demolition of kidney stones using focused shock waves. After decades of research, all it took was cutting a groove near the perimeter of the shock wave-focusing lens and changing its curvature.
"I've spent more than 20 years investigating the physics and engineering aspects of shock wave lithotripsy," said Pei Zhong, the Anderson-Rupp Professor of Mechanical Engineering and Materials Science at Duke University. "And now, thanks to the willingness of Siemens (a leading lithotripter manufacturer) to collaborate, we've developed a solution that is simple, cost-effective and reliable that can be quickly implemented on their machines."
The study appears online the week of March 17, 2014, in the Proceedings of the National Academy of Sciences.
The incidence of kidney stones in the United States has more than doubled during the past two decades, due at least in part to the expanding waistlines of its citizens. The condition has also been linked to hot, humid climates and high levels of stressa combination of living environments that seems to have led to a rise in kidney stone rates of veterans returning home from Iraq and Afghanistan.
During the past two decades, lithotripter manufacturers introduced multiple changes to their machines. Rather than having patients submerged in a bath of lukewarm water, newer machines feature a water-filled pouch that transfers the shock wave into the flesh. An electrohydraulic shock wave generator used in the past was replaced by an electromagnetic model that is more powerful, more reliable and more consistent.
The new designs made the devices more convenient and comfortable to use, but reduced the effectiveness of the treatment. After years of research, Zhong and his colleagues have determined why.
The increased power in some third-generation shock wave lithotripters narro
|Contact: Ken Kingery|